/***
 * Copyright 2002-2010 jamod development team
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ***/

package net.wimpi.modbus.msg;

import net.wimpi.modbus.io.Transportable;

/**
 * Interface defining a Modbus Message.
 * 
 * @author Dieter Wimberger
 * @version @version@ (@date@)
 */
public interface ModbusMessage extends Transportable {

	/**
	 * Sets the flag that marks this <tt>ModbusMessage</tt> as headless (for
	 * serial transport).
	 */
	public void setHeadless();

	/**
	 * Returns the transaction identifier of this <tt>ModbusMessage</tt> as
	 * <tt>int</tt>.<br>
	 * The identifier is a 2-byte (short) non negative integer value valid in
	 * the range of 0-65535.
	 * <p>
	 * 
	 * @return the transaction identifier as <tt>int</tt>.
	 */
	public int getTransactionID();

	/**
	 * Returns the protocol identifier of this <tt>ModbusMessage</tt> as
	 * <tt>int</tt>.<br>
	 * The identifier is a 2-byte (short) non negative integer value valid in
	 * the range of 0-65535.
	 * <p>
	 * 
	 * @return the protocol identifier as <tt>int</tt>.
	 */
	public int getProtocolID();

	/**
	 * Returns the length of the data appended after the protocol header.
	 * <p>
	 * 
	 * @return the data length as <tt>int</tt>.
	 */
	public int getDataLength();

	/**
	 * Returns the unit identifier of this <tt>ModbusMessage</tt> as
	 * <tt>int</tt>.<br>
	 * The identifier is a 1-byte non negative integer value valid in the range
	 * of 0-255.
	 * <p>
	 * 
	 * @return the unit identifier as <tt>int</tt>.
	 */
	public int getUnitID();

	/**
	 * Returns the function code of this <tt>ModbusMessage</tt> as <tt>int</tt>.<br>
	 * The function code is a 1-byte non negative integer value valid in the
	 * range of 0-127.<br>
	 * Function codes are ordered in conformance classes their values are
	 * specified in <tt>net.wimpi.modbus.Modbus</tt>.
	 * <p>
	 * 
	 * @return the function code as <tt>int</tt>.
	 * 
	 * @see net.wimpi.modbus.Modbus
	 */
	public int getFunctionCode();

	/**
	 * Returns the <i>raw</i> message as <tt>String</tt> containing a
	 * hexadecimal series of bytes. <br>
	 * This method is specially for debugging purposes, allowing to log the
	 * communication in a manner used in the specification document.
	 * <p>
	 * 
	 * @return the <i>raw</i> message as <tt>String</tt> containing a
	 *         hexadecimal series of bytes.
	 * 
	 */
	public String getHexMessage();

}// interface ModbusMessage
